Recently, a magnetic random access memory (MRAM) using tunneling magneto resistive (TMR) have been developed. The MRAM is configured with a magnetoresistive element including a magnetic tunnel junction (MTJ); therefore, a large magnetoresistance ratio is obtained.
In a recently discussed spin injection writing method, the direction of magnetization is reversed by injecting a current into a magnetoresistive element. When injecting a current into the magnetoresistive element, the current generally flows through a contact plug from a drain of metal-insulator-semiconductor field-effect transistor (MISFET). However, in this case, since the magnetoresistive element has parasitic resistances such as a contact resistance between the drain and the contact plug, a contact plug resistance itself, and a contact resistance between a contact plug and an electrode of the magnetoresistive element, the current value flowing to the magnetoresistive element from the drain may be small. This has confronted a problem that enough current can not be ensured to reverse the magnetization direction for the magnetoresistive element.